Pin 79 on the Graphics Chip

[spaced]

I was following the guide on mmmonkey for the 50/60hz mod, I've used the guides for my Mega Drive mods, but I've messed it up. I just could not get pin 79 to lift without trouble. When it did come up pin 80 came with it. I soldiered pin 80 back but during this pin 79 decided to make a dash for the exit and broke away.

After not too much swearing, kids in the room, I put it back together. Still works but I take it 50/60hz mod is no more?

What does pin 79 actually do as not needed to play games?

[buckoa51]

cgfm2.emuviews.com/txt/genvdp.txt

According to that it's data bus, which would definitely break your Megadrive. I didn't know you had to lift pins on the VDP to do a 50/60hz mod?!

[zyrobs]

See this is *exactly* why I don't recommend lifting that pin. There are billions of jumpers and trace points on practically all Sega consoles EXACTLY for this reason, so it's not a giant pain to do something as easy as region modification. This is to make manufacturing easier, and to make game developers' job easier (who actually would need such ability, in fact many Saturn dev systems had things like this built-in).

If that pin is not connected to anything, it pulls itself low, meaning the machine is locked into 50hz mode. The only thing you can do is to CAREFULLY file away the corner of the chip, exposing enough of the trace under the package, so you still have something to solder your switch to.

Feb 10, 2013 11:15:05 GMT buckoa51 said:

cgfm2.emuviews.com/txt/genvdp.txt

According to that it's data bus, which would definitely break your Megadrive. I didn't know you had to lift pins on the VDP to do a 50/60hz mod?!

You misread it; he used mmonkeys guides for his Megadrive, and now he tried his guides on the Saturn too.

[spaced]

buckoa51, as zyrobs said I meant I tried the mod on my Saturn not MD. MD mods worked Saturn attempt complete mess.

zyrobs, there was not much left to connect the wire to. I'll open it up again and see and maybe try and file it down a bit to see if I can get something to soldier onto.

[antime]

You know that most Saturn mainboards have an unpopulated footprint for a 50/60Hz switch right next to the backup battery? Even if you don't want to or can't use it, there are far easier locations to solder.

[zyrobs]

Feb 10, 2013 15:46:29 GMT antime said:

You know that most Saturn mainboards have an unpopulated footprint for a 50/60Hz switch right next to the backup battery? Even if you don't want to or can't use it, there are far easier locations to solder.

Only 4 PAL motherboards had that, out of those 2 are identical and on 1 that switch is dysfunctional.